WO2015099282A1 - Composite nonwoven fabric and preparation method therefor - Google Patents

Abstract

Provided are a composite nonwoven fabric and a preparation method therefor, the composite nonwoven fabric comprising: a nonwoven fabric base material formed, by electrospinning, of at least one or two types of fibers selected from the group consisting of copolymers of polylactic acid, polycaprolactone and lactic acid-glycolic acid; and a carboxymethylcellulose coating layer formed on both surfaces of the nonwoven fabric base material or in at least one of pores inside the nonwoven fabric base material, wherein the composite nonwoven fiber becomes opaque in a non-liquid absorbing state and becomes transparent in a liquid-absorbing state.

Description

Composite Nonwovens and Methods for Making the Same

The present invention relates to a composite nonwoven fabric and a method for producing the same, and more particularly, to a composite nonwoven fabric having a good liquid absorption and a high transparency at the time of absorption, and directly coated on the wound surface to serve as a temporary artificial skin and a method for producing the same. .

This application claims priority based on Korean Patent Application No. 10-2013-0166050, filed December 27, 2013, and all the contents disclosed in the specification and drawings of the application are incorporated in this application.

Skin not only protects the human body from various harmful environments such as microorganisms, ultraviolet rays, and chemicals, but also inhibits water evaporation, thereby preventing dehydration and regulating body temperature. to be.

On the other hand, as the industrial society develops, the possibility of skin damage due to various causes such as severe burns, trauma, wounds, bedsores and skin diseases is increasing. At this time, wounds that cannot be closed first are severe defects in which skin transplantation is inevitable. It can also leave.

Therefore, the repair of damaged skin tissue is a very important problem, and in order to promptly heal wounds and to minimize secondary side effects, wound treatment using an appropriate wound coating material is essential.

In particular, the skin of the human body has a property to protect the wound and to naturally heal when wounds, burns, etc. In this case, the wound covering material is used as a method to effectively protect the wound and to speed up the healing. The characteristics of wound coating should be excellent in biocompatibility, so that there is no rejection reaction to the wounded area, enough to absorb the body fluid discharged from the wounded area, and high moisture permeability to prevent the invasion of normal skin around the wound. It must be breathable to maintain.

Conventional thin-film wound coatings promote wound healing by keeping the wound moist, promoting dissolution of necrotic tissue and formation of granulation tissue, but by releasing too much body fluid and other discharges around the wound. The skin is crushed, the discharge leaked out there was a problem that should be discharged randomly. In addition, there is a disadvantage in that the pores must be additionally formed physically and chemically in order to improve moisture permeability.

In addition, the wound site was covered with the wound covering material, so that the wound healing process was not seen, the healing process could not be checked, and the wound infection or the need for replacement of the bandage could not be checked, so the wound covering material had to be removed. In this case, even if the wound is not sufficiently healed, the wound covering material is removed, which may cause serious problems such as damage to the skin and disruption of the healing process.

Therefore, there is still a need for development of a wound coating material having both liquid absorptivity and transparency to the discharge of the wound site.

The problem to be solved by the present invention is to provide a composite non-woven fabric having excellent liquid absorption and high transparency at the time of liquid absorption, is directly coated on the wound surface to serve as a temporary artificial skin.

Another object of the present invention is to provide a method for producing the composite nonwoven fabric.

Another object of the present invention is to provide a sanitary article using the composite nonwoven fabric described above.

In order to solve this problem, according to an aspect of the present invention,

Nonwoven substrates composed of one or two or more fibers selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers formed by electrospinning; And

It comprises a carboxymethyl cellulose coating layer formed on at least one of the two sides of the nonwoven fabric substrate or the internal pores of the nonwoven substrate,

A composite nonwoven fabric is provided that is opaque in the non-absorbed state and becomes transparent in the absorbed state.

The average pore size of the composite nonwoven fabric may be 5 μm or less.

The average diameter of the fibers may be 100 to 4,000 nm.

The lactic acid content of the lactic acid-glycolic acid copolymer may be 10 to 90 molar ratio.

The loading amount of the carboxymethyl cellulose coating layer may be 1 to 30 parts by weight based on 100 parts by weight of the nonwoven fabric substrate.

Transparency after absorbing the composite nonwoven fabric in 0.9% saline for 30 seconds may be 60% or more.

The liquid absorption ratio of the composite nonwoven fabric may be 4 g / g or more.

According to another aspect of the invention,

Preparing an electrospinning solution by dissolving one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers in a solvent;

Electrospinning the spinning solution to form a nonwoven substrate; And

There is provided a method for producing a composite nonwoven fabric comprising coating a carboxymethyl cellulose solution on the nonwoven substrate to form a carboxymethyl cellulose coating layer.

The carboxymethyl cellulose solution may be prepared by dissolving carboxymethyl cellulose in a mixed solvent of water and a non-solvent having a surface tension lower than that of the carboxymethyl cellulose.

The content of the non-solvent in the mixed solvent may be 5 to 60% by weight.

The method may further include calendering the nonwoven substrate after the electrospinning to form the nonwoven substrate before or after coating the carboxymethyl cellulose solution.

According to another aspect of the present invention, a sanitary article using the above-described composite nonwoven fabric is provided.

The hygiene article may be a medical coating, an absorbent hygiene article, a food packaging material, or a mask pack.

According to the present invention, a composite nonwoven fabric having excellent liquid absorptivity and high transparency at the time of liquid absorption, which is directly coated on the wound surface, serves as a temporary artificial skin, and can eliminate the problem of secondary infection by blocking bacterial penetration from an external infectious agent; Sanitary articles using the same can be provided.

The following drawings, which are attached to this specification, illustrate exemplary embodiments of the present invention, and together with the detailed description of the present invention, serve to further understand the technical spirit of the present invention. It should not be construed as limited to.

1 is a graph evaluating the hydrophilicity of the composite nonwoven fabric prepared in Example 1 and the nonwoven fabric prepared in Comparative Example 1. FIG.

2 and 3 are photographs showing the results of evaluating the transparency of the composite nonwoven fabric prepared in Example 1 and the nonwoven fabric prepared in Comparative Example 1 during liquid absorption.

4 is a photograph showing the results of comparative evaluation of the transparency of the liquid absorption of Example 1 and Comparative Example 3.

5 and 6 are SEM pictures of the surface of the composite nonwoven fabric prepared in Example 1 and Comparative Example 3, respectively.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention. Prior to this, terms or words used in the present specification and claims should not be construed as being limited to the common or dictionary meanings, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

Polylactic acid (PLA) refers to the entire polymer composed of lactic acid (Lactic acid) as a monomer, and is a polymer synthesized by using L-lactic acid, which is fermented by microorganisms from renewable resources such as polymer lactic acid and starch, as a monomer. Depending on the isomer D-Lactide and L-Lactide content and arrangement (random copolymerization, block copolymerization), thermal and physical properties may vary.

Lactic acid-glycolic acid copolymers (PLGA, polylactic-co-glycolic acid) are copolymers having a common repeating unit derived from polylactic acid and polyglycolic acid, respectively. At this time, the polyglycolic acid has a characteristic of being absorbed and degraded in vivo by aliphatic polyester having a very simple structural unit (-O-CH ₂ -CO-).

As a result, such polylactic acid and lactic acid-glycolic acid copolymers are generally used as medical products and biomaterials as biocompatible and biodegradable thermoplastic polyesters which are recognized worldwide.

However, the polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers are characterized as being hydrophobic or having a low degree of wettability, in whole or in part. Therefore, when polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers are used as a medical, in particular, wound covering material, the liquid absorption characteristics of the secretion discharged from the wound area are lowered, thereby adhering to the wound area, and as temporary artificial skin. There was a limit to not functioning enough. In addition, in order to prevent a second injury caused by an external infectious agent, the necessity of controlling the pore size and the like of the tissue is increased in developing a material using the polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymer. In addition to the improvement of the liquid absorption property, there is a further need for the need to easily observe the state of the wound site to enable timely treatment and treatment even when the wound site is applied.

In order to solve the demand for the latest various properties of such medical materials, the present inventors include a nonwoven substrate made of fibers of polylactic acid, polycaprolactone or lactic acid-glycolic acid copolymer formed by electrospinning; And a carboxymethyl cellulose coating layer formed on at least one of both surfaces of the nonwoven fabric substrate or the internal pores of the nonwoven fabric substrate, which is opaque in the non-absorbed state and transparent in the absorbed state.

The nonwoven substrate of the composite nonwoven fabric consists of one or two or more fibers selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers formed by electrospinning.

The polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers, as described above, provide excellent biocompatibility, biodegradability, and the like, which are basic properties of the composite nonwoven fabric.

At this time, the content of lactic acid in the lactic acid-glycolic acid copolymer may be adjusted to preferably 10 to 90 molar ratio, more preferably 10 to 70 molar ratio. In the case of adjusting the content of lactic acid, it is easy to prepare a solution for electrospinning, and the biodegradation property is improved, and biodegradation may occur well over time even if it remains on the wound surface.

In the present invention, the nonwoven substrate is formed of the fiber by electrospinning, which can thin the substrate while fully exhibiting the properties of biodegradable, biocompatible polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymer, This is because the pore size of the substrate can be easily adjusted, has high flexibility, and improves the coating property on the skin.

The fibers of the lactic acid, polycaprolactone and lactic acid-glycolic acid copolymers forming the nonwoven substrate have an average diameter of 100 to 4,000 nm, more preferably 500 to 3,000 nm. When the diameter of the fiber satisfies this range, the pore size of the substrate can be controlled sufficiently small without increasing the thickness of the nonwoven substrate, and the flexibility of the nonwoven fabric can be improved.

The composite nonwoven fabric according to the present invention includes a carboxymethyl cellulose coating layer on at least one of both sides of the nonwoven fabric substrate or internal pores of the nonwoven substrate.

The carboxymethyl cellulose coating layer improves hydrophilicity, liquid absorption, and the like by improving the disadvantages of the hydrophobic property of the nonwoven substrate made of one or two or more fibers selected from the group consisting of polylactic acid, polycaprolactone, and lactic acid-glycolic acid copolymers. And maintain a moist environment at the wound site. Also,

The loading amount of the carboxymethyl cellulose coating layer may be 1 to 30 parts by weight based on 100 parts by weight of the nonwoven fabric substrate. When the loading amount of the carboxymethyl cellulose coating layer satisfies this range, pore control is easily improved to improve the absorption characteristics of the final composite nonwoven fabric and to prevent bacterial invasion from external infectious agents.

The carboxymethyl cellulose coating layer may be coated on at least one surface of the nonwoven fabric substrate, or in accordance with the pore size control of the nonwoven substrate, carboxymethyl cellulose may be incorporated into the space inside the pores to form a coating layer. In particular, the greater the degree of penetration of the carboxymethyl cellulose coating layer into the voids inside the pores of the nonwoven fabric substrate, the better the liquid absorption characteristics as well as the surface of the nonwoven fabric substrate, thereby increasing the overall liquid absorption ratio of the nonwoven substrate. As a result, when the composite nonwoven fabric of the present invention is applied to the wound site, the absorption property to secretion such as body fluids is excellently improved, which may result in better wound healing.

The average pore size of the composite nonwoven fabric may be 5 μm or less, preferably 0.2 to 5 μm, more preferably 0.5 to 2 μm. The average pore size of this composite nonwoven fabric may be affected by the average size of the original nonwoven substrate and the loading amount and coating aspect of the carboxymethyl cellulose coating layer to be coated. In addition, if the calendering process is performed after the carboxymethyl cellulose coating layer is formed on the nonwoven fabric base, the average pore size of the composite nonwoven fabric can be controlled according to the conditions of the calendering process, that is, the temperature and the pressure.

When the average pore size of the composite nonwoven fabric satisfies this range, external infectious agents such as Staphylococcus aureus may fundamentally block access to the wound site through the composite nonwoven fabric, and may provide appropriate breathability.

The composite nonwoven fabric has a carboxymethyl cellulose coating layer on a nonwoven substrate made of one or two or more fibers selected from the group consisting of hydrophobic polylactic acid, polycaprolactone, and lactic acid-glycolic acid copolymers, thereby improving hydrophilicity, particularly absorption characteristics. It is characterized by being improved. Absorption characteristics of such a composite nonwoven fabric can be evaluated through the weight change before and after the absorption in the sample of a predetermined weight, as follows.

Absorption magnification (g / g) = [(weight of sample after absorption)-(weight of sample before absorption)] / (weight of sample before absorption)

The liquid absorption ratio of such a composite nonwoven fabric may be 4 g / g or more, preferably 4 to 30 g / g, more preferably 6 to 20 g / g. When the absorption ratio of the composite nonwoven fabric satisfies this range, the wound site is placed in an appropriate wet environment when coated on the wound site, and the body adhesiveness discharged from the wound site is absorbed to improve skin adhesion of the nonwoven fabric.

The composite nonwoven fabric according to the present invention has the property of being opaque in the non-absorbed state and transparent in the absorbed state. This property is due to the fact that the skin adhesion of the nonwoven fabric is improved and the scattering of light is reduced with absorption.

In general, if the skin is injured, it is important to look at how the wound is treated, so that proper treatment is possible. However, in order to observe the wound site, the normal nonwoven fabric has a problem of removing the wound covering made of the nonwoven fabric to observe the skin condition in order to observe the wound site. In this case, the wound site is not completely treated. Removing the wound covering can cause extreme pain for the patient.

In this regard, the transparency after absorbing the composite nonwoven fabric in 0.9% saline for 30 seconds may be 60% or more, preferably 60 to 95%, more preferably 75 to 90%. Transparency was compared using the Gretag Macbeth colorimeter (CE 3100) using the reflectance measurement method in the visible wavelength range of 400 ~ 700nm under the D65 standard light source by the following equation.

O _p = 100-Σ R _i / j

O _p : Transparency (%)

Reflectance corresponding to R _i = i ( i = 1 ~ j ) th wavelength

j = reflectance count

When the transparency of the composite nonwoven fabric satisfies this range, when the body fluid or saline solution is absorbed into the composite nonwoven fabric, the wound site may be easily observed even when the composite nonwoven fabric is attached.

In addition, when the composite nonwoven fabric is opaque in the non-absorbed state, it means that the transparency is less than 60% by the transparency measurement method.

The composite nonwoven fabric of the present invention may have a thickness of 50 to 500 μm, more preferably 100 to 300 μm. When satisfying the thickness range of the composite nonwoven fabric, it is advantageous to improve the transparency and flexibility of the nonwoven fabric.

According to another aspect of the present invention, a method for preparing a composite nonwoven fabric includes preparing a electrospinning solution by dissolving one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone, and lactic acid-glycolic acid copolymers in a solvent. step; Electrospinning the spinning solution to form a nonwoven substrate; And coating a carboxymethyl cellulose solution on the nonwoven substrate to form a carboxymethyl cellulose coating layer.

Electrospinning is used to produce the nonwoven substrate of the present invention. For electrospinning, one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers must be dissolved in a solvent to prepare an electrospinning solution.

In order to prepare the electrospinning solution in the present invention, the solvent used may uniformly dissolve one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers, and radioactive. Any of these high solvents can be used without limitation, examples being trifluoroacetic acid, dimethylformamide, dimethylsulfoxide, chloroform, trifluoroethylene, acetone, hexafluoroisopropanol, methylene chloride, tetrahydrofuran, acetic acid and formic acid Etc. may be used, and they may be used as one or two or more mixed solvents.

At this time, the content of one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymer added in the electrospinning solution is 5 to 20% by weight in the total electrospinning solution, more preferably. Preferably from 8 to 15% by weight. When the weight percentage is adjusted in this way, it is possible to obtain an electrospinning solution which is uniformly dissolved and has an appropriate viscosity and is easy to handle. As a result, spinning properties may be improved, and the diameter distribution of the manufactured fiber may be uniform.

Preferably, one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers are used as co-solvents of dimethyl formamide and chloroform with excellent emissivity for easy removal of residual solvents. It can be completely dissolved so that there are no impurities, and stirred at room temperature for about 12 hours before being used for electrospinning.

Next, the prepared electrospinning solution is electrospun to form a nonwoven substrate.

Conventional electrospinning systems and theories suggest that the electrospinning process must be performed under high voltage, and the air condition inside the chamber is also of great importance due to the nature of electrostatic spinning. As such, when the fiber is manufactured by a general process, due to the electrostatic process characteristics sensitive to the environment (temperature, humidity) of the spinning chamber, fine changes in the shape of the fiber are difficult to produce a reproducible material.

Particularly, polymers such as polylactic acid, polycaprolactone, or lactic acid-glycolic acid copolymers do not have a constant molecular weight due to their properties, so it is important to control process conditions when producing fibers by electrospinning.

The basic electrospinning device used in the present invention is equipped with a syringe fitted with 21G to 24G nozzles made of stainless steel in an integrally configured positive charge high voltage generator, an integrated drum and a metered discharge pump. In the present invention, after fabrication of each fiber sheet according to the concentration of solution, applied voltage, spinning distance, fluid velocity, etc., which have an important influence on fiber morphology among various process factors, the structure and morphology are analyzed and the best reproducible electrospinning condition is obtained. Applied.

In addition, the electrospinning device according to an embodiment of the present invention, the electrospinning solution prepared by dissolving one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymer in a solvent Any device capable of electrospinning may be applied without limitation, and examples thereof include a syringe type, a wire type, a drum type, and the like, but are not limited thereto.

In the present invention, the electrospinning is preferably carried out under the electrospinning conditions of 5 to 20% by weight of the mixed solution, voltage 5 to 100 kV, discharge rate of the solution of 0.1 to 10 ml / h and spinning distance of 3 to 50 cm. .

Next, the carboxymethyl cellulose solution is coated on the obtained nonwoven fabric substrate to form a carboxymethyl cellulose coating layer.

The carboxymethyl cellulose solution may be prepared by dissolving carboxymethyl cellulose in a mixed solvent of water and alcohol.

Typically, carboxymethyl cellulose is well soluble in water, whereas polylactic acid, polycaprolactone, or lactic acid-glycolic acid copolymers are hydrophobic. When coating a nonwoven substrate made of one or two or more fibers selected from the group consisting of coalescing, it is difficult to uniformly attach the aqueous solution of carboxymethyl cellulose to the nonwoven substrate. However, when the non-solvent having a lower surface tension than water and a non-solvent of carboxymethyl cellulose as a solvent is mixed, the surface tension of the resulting solution is lower than that of the aqueous solution, thereby uniformly coating the carboxymethyl cellulose solution on the nonwoven fabric substrate.

At this time, the content of the non-solvent in the mixed solvent is 5 to 60% by weight, more preferably 10 to 30% by weight. In this case, when the content of the non-solvent is less than 5%, the effect of adding the non-solvent is insignificant, and when the content of the non-solvent is greater than 60%, the non-solvent cannot dissolve the carboxymethyl cellulose. have.

As the non-solvent, alcohols such as methanol, ethanol, isopropyl alcohol, acetone, methylene chloride, chloroform, and the like may be used alone or as a mixture of two or more thereof.

At this time, when the carboxymethyl cellulose solution is coated on the nonwoven substrate, the coating amount of the carboxymethyl cellulose solution may be adjusted so that the loading amount of the carboxymethyl cellulose coating layer is 1 to 30 parts by weight based on 100 parts by weight of the nonwoven substrate. have.

The non-woven substrate coated with the carboxymethyl cellulose solution may be hot air dried or vacuum dried at room temperature or 40 to 120 ° C. to obtain a composite nonwoven fabric.

In addition, after the drying treatment, the obtained composite nonwoven fabric may be further subjected to a calendering process at a temperature of 200 to 600 psi at room temperature to 100 ° C. By passing through such a calendering process, the pore size and thickness of the finally obtained composite nonwoven fabric can be adjusted.

The composite nonwoven fabric of the present invention may be usefully used in various medical coatings, absorbent hygiene products, food packaging materials, mask packs, and the like, and may have particularly suitable properties as a wound coating material serving as a temporary artificial skin during burn treatment.

Hereinafter, examples will be described in detail to help understand the present invention. However, embodiments according to the present invention can be modified in many different forms, the scope of the invention should not be construed as limited to the following examples. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art.

Example 1

The lactic acid-glycolic acid copolymer (PLGA) (lactic acid: glycolic acid = 70:30 weight ratio) is dissolved in a mixed solvent of dimethylformamide (DMF) and chloroform (weight ratio = 1: 9) to 10% by weight to form an electrospinning solution. Ready.

Thereafter, a voltage of 15 kV, a spinning distance of 20 cm, and a fluid velocity of 6 ml / h were fixed using an electrospinning apparatus and spun for 5 hours on a rotating drum current collector to obtain a nonwoven substrate. Thereafter, the obtained nonwoven substrate was washed with ethanol and dried in a vacuum oven for 24 hours at room temperature to finally prepare a nonwoven substrate having an average pore size of 11.6 μm.

The prepared nonwoven fabric substrate was immersed in 0.4 wt% carboxymethyl cellulose solution prepared by dissolving carboxymethyl cellulose in a mixed solvent having a weight ratio of ethanol and water of 20:80 for 10 seconds, and then dried at 80 ° C. for 1 hour to average A composite nonwoven fabric having a pore size of 4.9 μm and a thickness of 159 μm was prepared. At this time, the loading amount of carboxymethyl cellulose was 21 parts by weight based on 100 parts by weight of the nonwoven fabric.

Example 2

The lactic acid-glycolic acid copolymer (PLGA) (lactic acid: glycolic acid = 70:30 weight ratio) is dissolved in a mixed solvent of dimethylformamide (DMF) and chloroform (weight ratio = 1: 9) to 10% by weight to form an electrospinning solution. Ready.

Thereafter, using an electrospinning apparatus, a voltage of 20 kV, a spinning distance of 20 cm, and a fluid velocity of 6 ml / h were fixed and spun on a rotating drum current collector for 6 hours to obtain a nonwoven substrate. Thereafter, the obtained nonwoven substrate was washed with ethanol and dried in a vacuum oven for 24 hours at room temperature to obtain a nonwoven substrate having an average pore size of 7 μm, which was then calendered at a pressure of 500 psi at room temperature, and the average pore size was 4.1 μm. The phosphorous nonwoven substrate was finally produced.

The prepared nonwoven fabric substrate was immersed in 0.4 wt% carboxymethyl cellulose solution prepared by dissolving carboxymethyl cellulose in a mixed solvent having a weight ratio of ethanol and water of 20:80 for 10 seconds, and then dried at 80 ° C. for 1 hour to average A composite nonwoven fabric having a pore size of 3.1 μm and a thickness of 104 μm was prepared. At this time, the loading amount of the carboxymethyl cellulose was 14 parts by weight based on 100 parts by weight of the nonwoven fabric.

Example 3

The lactic acid-glycolic acid copolymer (PLGA) (lactic acid: glycolic acid = 70:30 weight ratio) is dissolved in a mixed solvent of dimethylformamide (DMF) and chloroform (weight ratio = 1: 9) to 10% by weight to form an electrospinning solution. Ready.

Thereafter, using an electrospinning device, a voltage of 20 kV, a spinning distance of 19 cm, and a fluid speed of 6 ml / h were fixed and spun on a rotating drum current collector for 8 hours to obtain a nonwoven substrate. Thereafter, the obtained nonwoven substrate was washed with ethanol and dried in a vacuum oven for 24 hours at room temperature to prepare a nonwoven substrate having an average pore size of 5.4 μm.

The prepared nonwoven fabric substrate was immersed in 0.4 wt% carboxymethyl cellulose solution prepared by dissolving carboxymethyl cellulose in a mixed solvent having a weight ratio of ethanol and water of 20:80 for 10 seconds, and then dried at 80 ° C. for 1 hour to average A composite nonwoven fabric having a pore size of 1.9 μm and a thickness of 181 μm was prepared. At this time, the loading amount of the carboxymethyl cellulose was 20 parts by weight based on 100 parts by weight of the nonwoven fabric.

Example 4

Polycaprolactone was dissolved in a mixed solvent of methylformamide (DMF) and chloroform (weight ratio = 3: 7) to 12% by weight to prepare an electrospinning solution.

Thereafter, using an electrospinning apparatus, a voltage of 20 kV, a spinning distance of 20 cm, and a fluid velocity of 5 ml / h were fixed and spun on a rotating drum current collector for 6 hours to obtain a nonwoven substrate. The resulting nonwoven substrate was then prepared in a vacuum oven at 45 ° C. for 24 hours.

The prepared nonwoven fabric substrate was immersed in a 0.04 wt% carboxymethyl cellulose solution prepared by dissolving carboxymethyl cellulose in a mixed solvent having a weight ratio of ethanol and water of 30:70 for 10 seconds, and then dried at 40 ° C. for 30 minutes to average. A composite nonwoven fabric having a pore size of 4.6 μm and a thickness of 78 μm was prepared.

Comparative Example 1

A nonwoven substrate prepared in the same manner as in Example 1 was prepared except that the step of immersing the carboxymethyl cellulose solution was not performed.

Comparative Example 2

A nonwoven substrate prepared in the same manner as in Example 3 was prepared except that the step of immersing the carboxymethyl cellulose solution was not performed.

Comparative Example 3

A composite nonwoven fabric substrate was prepared in the same manner as in Example 1, except that only water was used instead of ethanol and water mixed solvent in the preparation of the carboxymethyl cellulose solution in the immersion treatment in the carboxymethyl cellulose solution.

Property evaluation

Average pore size measurement

Average pore size of the nonwoven fabric substrate, the composite nonwoven fabric prepared in Examples 1 to 3, and the nonwoven fabric substrate prepared in Comparative Examples 1 and 2 using a capillary flow porometer (CFP-1200AEL, Porous Materials Inc.) The size was measured.

Hydrophilicity Evaluation (Contact Angle)

The contact angle is measured based on the KS L 2110 standard using an image analyzer (Drop shape analysis system; DSA 100, KRUSS GmbH) using the image analyzer (Drop shape analysis system; DSA 100, KRUSS GmbH). It was. Using the above evaluation method, the hydrophilicity of the nonwoven fabrics prepared in Example 1 and Comparative Example 1 was evaluated, and the results are shown in FIG.

Absorption Magnification Evaluation

A sample of 3 cm 3 cm is cut out of the nonwoven fabric under standard conditions, and the weight is measured accurately. The sample is immersed in 0.9% saline for 30 seconds. Thereafter, one end of the nonwoven fabric is pulled out with tweezers, and then waited until the saline solution no longer drops, the weight at the time of liquid absorption is measured, and the liquid absorption ratio is calculated by the following equation.

Absorption magnification (g / g)

= [(Weight of sample after absorption)-(weight of sample before absorption)] / (weight of sample before absorption)

Using the above evaluation method, the absorption ratio of the nonwoven fabric prepared in Examples and Comparative Examples was evaluated, and the results are shown in Table 1 below.

Table 1

	Example 1	Example 2	Example 3	Example 4	Comparative Example 1	Comparative Example 2
Absorption magnification (g / g)	8.4	6.1	8.7	6.0	2.7	2.4

Transparency Evaluation on Absorption

(1) visual evaluation

After applying the composite nonwoven fabric prepared in Example 1 on the wound site and the substrate, the transparency was visually evaluated after the absorption of 0.9% physiological saline for 30 seconds (left picture) and after (right picture). Are shown in FIGS. 2 and 3, respectively.

After the nonwoven fabrics prepared in Example 1 and Comparative Example 3 were absorbed with 0.9% physiological saline for 30 seconds, transparency was visually evaluated, and a photograph of the observed non-woven fabric was shown in FIG. 4.

2 to 4, in the case of the composite nonwoven fabric of Example 1, after absorbing 0.9% physiological saline for 30 seconds, the transparency is significantly increased so that the coating object is completely visible, and instead of the solvent mixed with ethanol and water It can be seen that transparency is completely different from Comparative Example 3 in which a carboxymethyl cellulose solution was prepared using only water to form a carboxymethyl cellulose coating layer.

(2) Evaluation of transparency by reflectance measuring method

The composite nonwoven fabrics prepared in Examples 1 and 3 and the nonwoven substrates prepared in Comparative Examples 1 and 2 were absorbed in 0.9% physiological saline for 30 seconds, and then visible light wavelength range was measured under a D65 standard light source using a Gretag Macbeth colorimeter (CE 3100). It was compared by the following formula using the reflectance measurement method at phosphorus 400 to 700nm.

O _p = 100-Σ R _i / j

O _p : Transparency (%)

Reflectance corresponding to R _i = i ( i = 1 ~ j ) th wavelength

j = reflectance count

The results are shown in Table 2 below.

TABLE 2

	Example 1	Example 2	Example 3	Example 4	Comparative Example 1	Comparative Example 2
Transparency (%)	80.8	83.3	82.0	80.8	55.6	37.1

(3) surface observation of composite nonwoven fabric

SEM photographs of the surfaces of the composite nonwoven fabrics prepared in Example 1 and Comparative Example 3 are shown in FIGS. 5 and 6, respectively.

Referring to FIGS. 5 and 6, when the solvent used in the carboxymethyl cellulose solution for forming the carboxymethyl cellulose coating layer is a mixed solvent of water and ethanol, the carboxymethyl cellulose penetrates uniformly between the electrospun fibers while the water It can be seen that the carboxymethyl cellulose is very nonuniformly distributed in a part of the sole solvent. This is because the nonwoven fabric made of the electrospun biodegradable polymer exhibits hydrophobicity, and when the water having a large surface tension is used as the sole solvent, the hydrophilicity is large, making it difficult to penetrate the aqueous solution of carboxymethyl cellulose. On the other hand, when the alcohol and water mixed solvent is used, the surface tension is lowered, thereby facilitating the penetration between the hydrophobic nonwoven fabrics.

Claims (14)

1. Nonwoven substrates composed of one or two or more fibers selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers formed by electrospinning; And

   It comprises a carboxymethyl cellulose coating layer formed on at least one of the two sides of the nonwoven fabric substrate or the internal pores of the nonwoven substrate,

   A composite nonwoven fabric that is opaque in the non-absorbed state and becomes transparent in the absorbed state.
2. The method of claim 1,

   Composite nonwoven fabric, characterized in that the average pore size of the composite nonwoven fabric is 5 ㎛ or less.
3. The method of claim 1,

   Composite nonwoven fabric, characterized in that the average diameter of the fiber 100 to 4,000 nm.
4. The method of claim 1,

   The composite nonwoven fabric, characterized in that the lactic acid content of the lactic acid-glycolic acid copolymer is 10 to 90 molar ratio.
5. The method of claim 1,

   Composite woven fabric, characterized in that the loading amount of the carboxymethyl cellulose coating layer is 1 to 30 parts by weight based on 100 parts by weight of the nonwoven fabric base.
6. The method of claim 1,

   The composite nonwoven fabric is characterized in that the transparency after absorbing the composite nonwoven fabric in 0.9% saline for 30 seconds 60% or more.
7. The method of claim 1,

   The liquid absorption ratio of the said composite nonwoven fabric is 4 g / g or more, The composite nonwoven fabric characterized by the above-mentioned.
8. Preparing an electrospinning solution by dissolving one or two or more mixtures selected from the group consisting of polylactic acid, polycaprolactone and lactic acid-glycolic acid copolymers in a solvent;

   Electrospinning the electrospinning solution to form a nonwoven substrate; And

   A method for producing a composite nonwoven fabric comprising coating a carboxymethyl cellulose solution on the nonwoven substrate to form a carboxymethyl cellulose coating layer.
9. The method of claim 8,

   And the carboxymethyl cellulose solution is prepared by dissolving carboxymethyl cellulose in a mixed solvent of water and a non-solvent having a surface tension lower than that of water and a nonsolvent of the carboxymethyl cellulose.
10. The method of claim 9,

    Method for producing a composite nonwoven fabric, characterized in that the content of the non-solvent in the mixed solvent is 5 to 60% by weight.
11. The method of claim 9,

    The non-solvent of the carboxymethyl cellulose is at least one member selected from the group consisting of alcohol, acetone, methylene chloride, and chloroform.
12. The method of claim 8,

    And calendering the nonwoven substrate after the electrospinning to form the nonwoven substrate before or after coating the carboxymethyl cellulose solution.
13. A hygiene article comprising the composite nonwoven of claim 1.
14. The hygiene article according to claim 13, wherein the hygiene article is a medical coating, an absorbent hygiene article, a food packaging material, or a mask pack.

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